Test QB: KOEO DTC P0603, P1605 Or KOEO, KOER & Continuous Memory DTC P1633: Testing

WARNING: This page does not describe the selected car, but rather 25 other vehicles, including the 2002 Lincoln Town Car, 2002 Lincoln Navigator, 2002 Lincoln LS, 2002 Lincoln Continental, and 2002 Lincoln Blackwood. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION table of fault code setting condition.

FAULT CODE SETTING CONDITION

Fault Code	KOEO	KOER	Continuous Memory
P0603	QB1
P1605	QB1
P1633	QB1	QB1	QB1

NOTE: For additional testing information, see DIAGNOSTIC AIDS .

NOTE: KAPWR is interrupted when PCM or battery is disconnected. DTC P0603, P1605 or P1633 may be generated during next PCM power-up.

1) DTC P0603, P1605 & P1633: Check Battery Terminals
Inspect battery terminals for corrosion or loose connection. Service as necessary. If battery terminals are okay, go to next step.

2) Check Engine Compartment For Proper Wire Routing

Inspect wiring harness and connectors for damage or corrosion. Ensure wiring harness is properly routed and not too close to ignition or exhaust components. Service as necessary. If no concerns are found, go to next step.

3) Check Keep Alive Power Circuit To PCM

Turn ignition switch to OFF position. Disconnect PCM connector(s). Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Using a DVOM, measure voltage between chassis ground and KAPWR circuit at PCM harness connector terminal No. 55 (104-pin PCM), or terminal No. A44 (150-pin PCM). While observing DVOM, wiggle and bend small sections of wiring harness between PCM and dash panel. If voltage is continuously 10.5 volts or more, go to next step. If at anytime voltage drops to less than 10.5 volts, isolate open in KAPWR circuit and repair as necessary.

4) Check For Repeat Of DTC P0603, P1605 Or P1633

Reconnect PCM connector(s). Start engine and allow to idle and reach normal operating temperature. Perform KOEO ON-DEMAND SELF-TEST . Retrieve Continuous Memory DTCs. If DTC P0603, P1605 or P1633 is present, replace PCM. If any other DTCs are present, service as necessary. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are present, testing is complete. DTC P0603, P1605 or P1633 may have been due to a previous repair.